Warp knitting machine

ABSTRACT

In a warp knitting machine with bipartite knitting needles respectively having a hook part and a latch part and provided with at least one needle bar for the hook parts and at least one latch bar for the latch parts of the needles, there is included a control device for controlling movement of the latch bar, the control device comprising means for uniformly and non-uniformly varying movements of the latch parts in opening and closing the hook parts of the knitting needle, for each course knitted in the warp knitting machine.

United States Patent Peschl et al.

[ 1 Sept. 5, 1972 [54] WARP KNITTING MACHINE [72] Inventors: ErvinPeschl, Ceska; Jan Skrepek,

Post Habrovany, both of Czechoslovakia [73] Assignee: W. Schlafhorst &Co., Monchengladbach, Germany, Vyzkumny Ustav Pletausky, Brno, Czechoslovakia [22] Filed: Dec. 5, 1969 [21] Appl. No.: 882,671

[30] Foreign Application Priority Data Dec. 6, 1968 Czechoslovakia..832068 [52] US. Cl. ..66/86 R [51] Int. Cl. ..D04b 23/00 [58] Field ofSearch ..66/l20, 154, 86, 87

[56] References Cited UNITED STATES PATENTS 2,775,108 12/1956 Belli..66/86 2,796,606 6/1957 Amidon ..66/120 Primary Examiner-RonaldFeldbaum Attorney-Curt M. Avery, Arthur E. Wilfond, Herbert L. Lernerand Daniel J. Tick 57 ABSTRACT In a warp knitting machine with bipartiteknitting needles respectively having a hook part and a latch part andprovided with at least one needle bar for the hook pans and at least onelatch bar for the latch parts of the needles, there is included acontrol device for controlling movement of the latch bar, the controldevice comprising means for uniformly and non-uniformly varyingmovements of the latch parts in opening and closing the hook parts ofthe knitting needle, for each course knitted in the warp knittingmachine.

11 Claims, 15 Drawing Figures PATENTEDSEP S19v2 3.688.524 snm 1 or i (AWL PATENTEBsEP 5 I972 SHEET 3 [1F 7 FIG.3

INVENTORS:

PAIENTEQSEP 6I972 3.688.524

SHEEI II III 7 F IGAO IROTATION OF THE MAIN SHAFT OF THE MACHINE NOSTITCH FORMATION-TUCK BACKING OFF-STITCH FORMATION FIGAb IROTATION OFTHE NEEDLE BAR CONTROL CAM I NO STITCH FORMATION-TUCK BACKING OFF-STITCHFORMATION IR OTATION OF THE LATCH BAR CONTROL CAM F|G.4c

STITCH FORMATION STITCH FORMATION ..s STITCH FORMATION TUCK T IIROTATION= ICOURSE OF STITCHES INVENTORS:

PATENTEB E 5 i972 SHEET 5 [IF 7 THREAD FILLING o a 6 OF THE DEVICEmyENToRs- 5m? SHEET 6 OF 7 FIG.7Q

THREADFILLING o H I I I I I II In OFTHEDEVICE: :-T T-T-I.I.Tg

INVENTORS NPNDINDINPNPNP m FIG 10 WARP KNITTING MACHINE Our inventionrelates to warp knitting machine such as warp frame Raschel knittingmachine, sewingknitting machine or the like, more particularly of thetype having bipartite knitting needles respectively having a hook partand a latch part and provided with at least one needle bar for hookparts and at least one latch bar for the latch part of the needles.

In the heretofore known warp knitting machines of this type, eachtwo-part knitting needle is formed of a hook part having a shaft that ishollow or that is formed with a groove and a latch part which isdisplaceably mounted in the hollow or groove of the hook part. By meansof a controlled reciprocal motion of the needle bar and the latch bar,the hooks of the knitting needles are alternately opened and closed asrequired by the cycle of the stitch forming and the production of arelated warp knitted fabric or web. In the heretofore known warpknitting machines or the like provided with bipartite knitting needles,all hook parts are secured on a needle bar and all latch parts on alatch bar. Owing to this structure, all of the knitting needles operatesimultaneously. All machines of this type are furnished with adisplacement mechanism which controls the mutual reciprocatory movementof the needle bar and the latch bar so that the hooks of the bipartiteknitting needles, when forming each course of the knitted fabric, areclosed in the knocking-over position and are opened in the position inwhich the thread is to be filled.

The number of patterns that are possible to be knitted with such warpknitting machines or the like is consequently considerably reduced. Itis in fact known, by employing various auxiliary patterning mechanisms,such as drop plates, patterning presses and the like, to attain agreater number of possible patterns on such machines; however, thesemechanisms are relatively complex and costly and furthermore placeincreased demands on survicing of the machine.

It is accordingly an object of our invention to provide a warp knittingmachine which avoids the foregoing disadvantages of the heretofore knownmachines of this general type and which more particularly affords aconsiderable increase in the possible number of patterns attainable withwarp knitting machines or the like without requiring auxiliarypatterning mechanisms.

With the foregoing and other objects in view we provide according to ourinvention, in a warp knitting machine with bipartite knitting needlesrespectively having a hook part and a latch part and provided with atleast one needle bar for the hook parts and at least one latch bar forthe latch parts of the needles, control device for controlling movementof the latch bar, the control device comprising means for uniformly andnon-uniformly varying movements of the latch parts in opening andclosing the hook parts of the knitting needle, for each course knittedin the warp knitting machine. It is thereby possible to control themovements of the bipartite knitting needles during the production ofcourses in such a way that the knitting needles form stitches in onecourse and form no stitches in another course.

In accordance with further features of our invention, the control devicecomprises at least two control cams rotatable at the same rotary speedfor actuating the latch parts on the one hand and the hook parts on theother hand, the control cam for controlling the displacements of thehook parts being formed with a greater number of lifter lobes than thecontrol cam for controlling the displacements of the latch parts. If,for example, in such a construction according to the invention, thecontrol cam for controlling displacements of the latch parts is providedwith a single lifter lobe and the control cam for the hook parts of theneedles is provided with two lifter lobes, the hook parts are twicereciprocatingly displaced and the latch parts only once for one rotationof the control cams, that is during the formation of one course. Thehook parts are thereby at the knocking-over location and then also formonly one stitch. In accordance with an added feature of the invention,the control device comprises control cams rotatable at varying rotaryspeeds, the control cam for controlling the displacements of the latchparts being rotatable at a lower rotary speed than the control cam forcontrolling the displacements of the hook parts.

ln accordance with yet another feature of the invention, the controldevice is formed of a control chain having individual control membersinstead of a control cam.

In accordance with concomitant features of our invention we provideanother embodiment thereof wherein the control device comprises at leastone patterning disc or wheel having a periphery divided into a pluralityof control fields or domains, each of the control fields controlling thedisplacement of the latch parts for each course being knitted. Inaccordance with other features of the invention included in anotherembodiment thereof which affords the attainment of a greater number ofpatterning possibilities, the latch bar is divided into two parts alongthe length of the working width thereof, the displacements of each partof the latch bar being controllable individually and independently ofone another by means of control device such as control eccentrics,control cams, chains or patterning discs or wheels.

The control device of our invention is advantageous both for warpknitting machines as well as for sewingknitting machines. In the lattercase, when the knitting needles are displaced into the position whereinthread is filled or drawn in, the knitting needles interweave the basematerial such as for example a fibrous fleece, a web, a foil and thelike, and the hook parts are provided with points.

In addition, a warp knitting machine or similar machine constructed inaccordance with the invention permits the production without auxiliarydevices of warp fabrics with patterns or designs formed by blindfilling, with patterns similar to pressed patterns and drop platepatterns, and with crepe patterns, and also the production of loopingplush as well as combinations of the aforementioned patterns or designsin a knitted fabric.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin warp knitting machine, it is nevertheless not intended to be limitedto the details shown, since various modifications and structural changesmay be made therein without departing from the spirit of the inventionand within the scope and range of equivalents of the claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawings, in which:

FIG. 1 is a diagrammatic elevational view partly in section of a warpknitting machine constructed in accordance with our invention whereinthe latch bar is controlled by control cams;

FIG. 2 is a view similar to that of FIG. I of another embodiment of thewarp knitting machine of our invention wherein displacement of the latchbar is controlled by a control cam rotatable at one half the rotaryspeed at which the control cam for controlling the displacement of theneedle bar is rotatable;

FIG. 3 is another view similar to that of FIGS. 1 and 2 of a furtherembodiment of the invention wherein displacement of the latch bar iscontrolled by a chain;

FIGS. 4a to 4c show characteristic curves of the displacements of theneedle bar and the latch bar;

FIGS. 5 and 5a respectively show a pattern and the thread filling for aknitted fabric with a four guide bar pattern;

FIG. 6 shows a four guide bar design or pattern with foundation weavesin a fringed pattern;

FIGS. 7 and 7a respectively show a pattern and the thread filling for atwo-bar three guide bar pattern;

FIG. 8 shows a smooth warp knitted pattern combined with a loopedpattern;

FIGS. 9 and 9a respectively show a pattern and the thread filling for athread guide bar pattern with tricot foundation pattern; and

FIG. 10 is a sewn fabric with warp knitted pattern.

Referring now to the drawings and first particularly to FIG. 1 thereof,there is shown therein an embodiment of the warp knitting machine of ourinvention having bipartite knitting needles I, referred to hereinaftermerely as knitting needles. The knitting needles I are respectivelyformed of a hook part 2 having a hollow stem in which a latch part 3 isguidingly displaceable. The hook parts 2 (only one shown in FIG. 1) arecast in lead members 4 which are fastened by screws 5 to a needle bar 6which is in turn mounted by means of screws 7 on two guide pins 8 whichare slidably displaceable in bearings 9 fastened by screws 10 to asupport 11. The needle bar 6 performs an upward and downwardreciprocatory movement in the direction of a double headed arrow S and SThe latch parts 3 of the knitting needles 1 are cast in lead members 12that are fastened by screws 13 to a latch bar 14 which is in turnmounted by means of screws 15 to guiding pins 16 that are slidablydisplaceable in bearings 17 fastened by screws 18 to the support 11. Thelatch bar 14 also performs a reciprocatory movement upwards anddownwards in direction of the double headed arrow S and S Each guide pin8 is connected by a pin 19 with a pull rod 20 which is in turn connectedby a pin 21 with a rocking lever 22. The rocking lever 22 swings orrocks about a bar or shaft 23 carried by holders 24 (only one of whichis shown in FIG. 1) which are fastened by screws 25 to a support 26. Therocking lever 22 carries a pin 27 on which a roller 28 is rotatablymounted. The roller 28 is controlled by and follows the surface of acontrol cam 81 provided with two lifter lobes 82 and 83. The cam 81 isfastened on to a shaft 30 which is mounted in bearings 31 screwed byscrews 32 to the support 26.

The guide pin 16 is connected by the pin 33 to the pull rod 34 which isin turn secured by a pin 35 to an oscillating or rocking lever 36 whichrocks or swings about the fixedly'mounted rod or pivot 23. A roller 37is rotatably mounted on the pin 35 and is controlled or follows thesurface of a control cam 38 mounted on the shaft 30.

Warp threads 39 and 40 are unwound from the warp beams 41 and 42respectively and are guided over back rests 43 and 414 to eye needles 45and 46 which are cast in lead members 47 and 48 and which are secured onguide bars 49 and 50 respectively.

The knitting needles 1 are guided in sinkers 51 of a knocking-over bar.Knitted fabric 53 is withdrawn by three draw-off rollers 54, 55 and 56and are wound into a package 57. Side walls 58 (only one shown in FIG.I) of the knitting machine are connected by the supports 1 I and 26which extend transversely therebetween.

In the embodiment of FIG. 2, the displacement mechanism of the warpknitting machine which controls the latch bar M differs from thedisplacement mechanism of the warp knitting machine shown in FIG. I inthat the control cam 38 which controls the roller or follower 37 ismounted on and firmly connected to its own shaft 59 which is rotatablymounted in bearings 60 which are in turn fastened by screws 61 toconnecting supports 62 extending transversely between and secured to theside walls 58 of the knitting machine. In FIG. 2 the roller 37 isrotatably mounted on the pin 35, as in the embodiment of FIG. 1, the pin35 being carried by the oscillating lever 36 which differs in theembodiment of FIG. 2 by the fact that it is longer than the oscillatinglever 36 of FIG. 1. A gear 63 is fixedly connected to the shaft 30 andmeshes with a gear 64 fixedly mounted on the shaft 59.

In the embodiment of FIG. 3, there is shown a warp knitting machinewherein the displacement mechanism which controls the latch bar 14includes a rotatable drum 65 that is mounted on and fixedly connected toa shaft 66. This rotatable drum 65 carries control members 67 which areconnected to one another by pins 68 in a manner conventional with theconnection of the links of a chain. As can be readily seen in FIG. 3,the control members 67 differ from the remaining conventional links ofthe chain carried by the drum 65 in that they are formed with raisedlobe-like parts which cause the roller 37 to lift as the lobe-like partspass thereunder. The shaft 66 is rotatably mounted in bearings 69 whichare fastened by means of screws 70 to a support 71 which extendstransversely between and connects the side walls 58 of the warp knittingmachine. The oscillating or rocking lever 36 carrying the roller 37oscillates about a bar or pivot 72 which is fixedly mounted and which iscarried by a support 73. The support 73 is fastened by screws 74 to aconnecting support 75 extending transversely between and secured to theside walls 58 of the knitting machine. Supports 77 (only one shown inFIG. 3) are also mounted on the connecting support 75 by screws 76 andcarry a nonrotatably mounted rod or pivot 78 about which arms 73 (onlyone of which is shown in FIG. 3) oscillate. The

arms 79 are provided at an end thereof with respective pins 80 on whichrollers 28 (only one of which is shown in FIG. 3) are rotatably mountedand are controlled by and follow the control cam 29.

The embodiment of the warp knitting machine shown in FIG. 1 operates inthe following manner:

The starting position for the formation of a course of knitted fabric isthe phase wherein the needle bar 6 furnished with hook parts 2 and thelatch bar 14 provided with latch parts 3 are located in the lowerknocking-over position. The displacement mechanism of the warp knittingmachine controlled by the control cam 81 which is provided with twolifter lobes 82 and 83 lifts the needle bar 6 from the lowerknocking-over position in direction of the arrow S into the upperposition for thread laying wherein the eye needles 45 and 46 lay warpthreads 39 and 40 into the hooks of the hook parts 2 of the knittingneedles 1. Thereafter, the needle bar 6 drops to the lower knocking-overposition. The latch bar 14 remains in the lower knocking-over positionbecause the rotatable control cam 38 does not lift the roller 37 in thisphase. Consequently, the hook part 2 of the knitting needle 1 remainsopen during knocking-over so that the knitting needle 1 forms a tuck.The needle bar 6 is then lifted again by the further-rotating controlcam 81 into the position for thread-laying wherein laying of the warpthreads 39 and 40 into the hook parts 2 of the knitting needles 1 takesplace, whereafter the needle bar 6 is again lowered into theknocking-over position. Meanwhile, the latch bar 14 is raised by thecontrol cam 37 upwardly into the closed position of the knitting needles1 wherein the latch parts 3 close the hook parts 2 of the knittingneedles 1 whereupon knocking-over occurs and the knitting needles 1 formstitches.

In FIG. 4a there are shown the displacements of the needle bar 6 and thelatch bar 14. During one rotation of the main shaft of the warp knittingmachine, the control cam 81 with both lifter lobes 82 and 83 thereofeffects two liftings of the needle bar 6 represented by thecharacteristic curve A, and the control cam 38 effects one lifting ofthe latch parts 3, as shown by the characteristic curve B, which closesthe hook parts 2 of the knitting needles 1 only for each second liftingof the needle bar 6.

In the embodiment shown in FIG. 2, the displacement of the needle bar 6is controlled by the simple control cam 29 so that for each rotation ofthe main shaft, a lifting of the needle bar 6 is effected. Nevertheless,the rotations of the control cam 38 for the latch bar 14 are only halfthe number of rotations of the control cam 29, due to the fact that thegear ratio of the gears 63 and 64 is 1:2, so that the latch bai 14 islifted only for each second lifting of the knitting needles 1, the hookparts 2 consequently being closed only in each second knitted courseduring knocking-over.

In FIG. 4b there are shown by characteristic curves similar to those ofFIG. 4a, the displacements of the needle bar 6 and the latch bar 14 forthe embodiment of the warp knitting machine of FIG. 2.

In the embodiment of the warp knitting machine of our invention shown inFIG. 3, the displacements of the needle bar 6 are controlled by thesimple control cam 29 and the displacements of the latch bar 14 by achain, each control member 67 of the chain controlling the displacementof the latch bar 14 when forming a knitted course. The desired ratio ofthe rotary speed of the control cam 29 to the rotary speed of the drum65 is provided by a conventional non-illustrated transmission system.The sequence of displacements of the needle bar 6 and the latch bar 14in the corresponding sequential courses is represented by characteristiccurves in FIG. 40. During a course in which boththe hook part 2 as wellas the latch part 3 are lifted, stitching is formed. In courses whereinonly hook parts 2 are lifted, only tucks are formed. The control cams 29and 81 of the needle bar 6 and the control earns 38 of the latch bar 14as well as the control chain having the control members 67 can bereplaced by patterning discs or wheels for specific types of knittedfabrics.

A sewn fabric can also be produced in the aforementioned warp knittingmachines or similar machines if the hook parts 2 of the knitting needle1 are provided with points and the needles interweave a fibrous fleeceor a similar foundation material.

FIGS. 5 and 5a show respectively the pattern and the drawing-in orthread filling for a fabric with four guide bar pattern. In this case,as shown in FIG. 5a, the first guide bar I is provided with a basicdrawing-in or thread filling of 1:1 i.e., one eye needle is full and oneis empty, and forms an open fringed pattern in each second row orcourse. The second guide bar II similarly has a drawing-in or threadfilling 1:1 i.e., one eye needle full and one empty, alternatelyefi'ecting weft filling and blind or blank filling so that this guidebar II forms no stitches but rather fills weft in each uneven course andforms loops in every even course. In FIG. 5, the courses in whichstitches are formed are denoted by the letter P and the courses whereinthe knitting needles form no stitches are denoted by the letter N. Thewarp threads of the second guide bar II form the thread system for thefoundation pattern. The third and fourth guide bars III and IV lay, bylateral displacement, stationary threads in longitudinal direction inthe foundation weave.

The four guide bar weave in FIG. 6 shows a foundation weave in fringedpattern which is joined or connected in one row by weft and in thesecond row by loops. The stationary threads in longitudinal directionare interwoven through the connecting weft of the foundation weave, infact alternately on the upper and lower side of the fabric.

FIGS. 7 and 7a show respectively a pattern and the drawing-in or threadfilling for a two-bar three guide bar pattern. As shown in FIG. 7a, thefirst guide bar I has a drawing-in or a thread filling ratio of 1:1i.e., one eye needle is full and one empty, and the second and thirdguide bars II and III have patterning drawing-in or thread filling. Thefirst guide bar I of FIG. 7a carries out the foundation pattern andforms on the forward needle bar an Atlas pattern wherein each reversecourse forms loops by blind or blank drawing-in or filling while theother courses are formed of stitches. In FIG. 7, the letters P denotethat the stiching needles form stitches, and the letters N denote thatthey form no stitches in the respective courses. The second guide bar IIwith the patterning drawing-in or thread filling thereof, as shown inFIG. 7a, lays stationary threads in longitudinal direction in conformitywith the foundation weave. The third guide bar I lays the threadsdrawn-in or filled in a pattern thereby into the stitching needles ofthe referred needle bar, where it forms loops, while the same guide barIII lays weft on the forward needle bar.

The blind or blank drawing-in or filling and the conforming displacementof the stationary threads permit the production of a warp knitted weavecombined with looping patterns, this combined weave being interwoven onthe underside thereof uniformly in transverse direction by weft-formingthreads of the loops, and on the upper and lower sides thereof in thelongitudinal direction by stationary threads between the small rods ofthe stitches, as shown especially clearly in FIG. 8. In diagonal andtransverse direction, firmness is imparted to this weave by the loopsthat are drawn-in or filled blind. FIGS. 9 and 9a show respectively apattern and the drawing-in or thread filling for a three guide barpattern. As shown in FIG. 9a, the first guide bar I provides adrawing-in or thread filling at a 1:1 ratio i.e., one eye needle is fulland one empty, the second and third guide bars II and III havingdrawing-in or thread filling ratios of 1:3 i.e., one eye needle full andthree eye needles empty. The first guide bar 1 produces the foundationpattern, forming a tricot pattern wherein closed and open courses orrows alternate. The open filling is blind, the closed forms stitches. InFIG. 9, the letters P accordingly denote the formation of stitches bythe stitching needles and the letters N denote, on the other hand, noformation of stitches by the stitching needles in the respectivecourses. The second and third guide bars II and III alternatelyinterweave stationary threads through the tricot pattern. The conformeddisplacement of the stationary threads and the blind drawing-in orthread filling of the foundation weave permit the production of a smoothwarp knitted weave, ash shown in FIG. 10, on a foundation material bythe application of a sewing-knitting machine constructed in accordancewith our invention. In this case, stationary or standing threads arealternately interwoven with the foundation weave on the upper side ofthe sewn fabric. The knitted fabric patterns shown for example in FIGS.through 10 demonstrate quite clearly the advantage attainable by thedevice of our invention over warp knitting machines or the like knownheretofore.

We claim:

1. In a warp knitting machine with bipartite knitting needlesrespectively having a hook part and a latch part, and provided with atleast one needle bar for the latch part, and provided with at least oneneedle bar for the hook parts and at least one latch bar for the latchparts of the needles, control device for controlling movement of thelatch bar, said control device comprising means for uniformly andnon-uniformly varying movements of said latch parts in opening andclosing the hook parts of the knitting needle, so as to selectively formstitches in one course knitted in the warp knitting machine and nostitches in another.

2. Control device according to claim 1 comprising at least two rotarycontrol members rotatable at given speed for respectively actuating thelatch parts, on the one hand, and the hook parts, on the other hand, thecontrol member for actuating the hook parts having more lifting lobesthan the control member for actuating the latch parts.

3. Control device according to claim 2 wherein at least one of saidrotary control members comprises a control chain having individualcontrol links formed with lifting lobes.

4. Control device according to claim 3 wherein at least another of saidrotary control members comprises a control cam.

5. In a warp knitting machine with bipartite knitting needlesrespectively having a hook part and a latch part, and provided with atleast one needle bar for the hook parts and at least one latch bar forthe latch parts of the needles, control device for controlling movementof the latch bar, said control device comprising means for uniformly andnonuniformly varying movements of said latch parts in opening andclosing the hook parts of the knitting needle, for each course knittedin the warp knitting machine, and at least two rotary control membersrotatable at different speeds for respectively actuating the latchparts, on the one hand, and the hook parts, on the other hand, thecontrol member for actuating the latch parts being rotatable at a slowerspeed than the control member for actuating the hook parts.

6. Control device according to claim 5 wherein at least one of saidrotary control members comprises a control chain having individualcontrol links.

7. Control device according to claim 6 wherein at least another of saidrotary control members comprises a control cam.

8. Control device according to claim 1 comprising at least onepatterning disc having a peripheral surface divided into a plurality ofcontrol fields, each of said control fields being adapted to controldisplacement of the latch parts for each course knitted.

9. Warp knitting machine according to claim I wherein the latch bar isdivided into at least two parts along the length of the operating widththereof, said control device comprising separate control members forrespectively controlling displacement of each of the parts of the latchbar individually and independently of one another.

10. In a warp knitting machine with bipartite knitting needlesrespectively having a hook part and a latch part, and provided with atleast one needle bar for the hook parts and at least one latch bar forthe latch parts of the needles, control device for controlling movementof the latch bar, said control device comprising means for uniformly andnon-uniformly varying movements of said latch parts in opening andclosing the hook parts of the knitting needle, for each course knittedin the warp knitting machine, and at least two control cams rotatable atthe same speed for respectively actuating the latch parts, on the onehand, and the hook parts, on the other hand, the control cam foractuating the hook parts having more lifting lobes than the control camfor actuating the latch parts.

11. In a warp knitting machine with bipartite knitting needlesrespectively having a hook part and a latch part, and provided with atleast one needle bar for the hook parts and at least one latch bar forthe latch parts of the needles, control device for controlling movementof the latch bar, said control device comprising means for uniformly andnon-uniformly varying movements of said latch parts in opening andclosing the hook parts of the knitting needle, for each course knittedin the warp knitting machine, and at least two control cams rotatable atdifferent speeds for respec-

1. In a warp knitting machine with bipartite knitting needlesrespectively having a hook pArt and a latch part, and provided with atleast one needle bar for the latch part, and provided with at least oneneedle bar for the hook parts and at least one latch bar for the latchparts of the needles, control device for controlling movement of thelatch bar, said control device comprising means for uniformly andnon-uniformly varying movements of said latch parts in opening andclosing the hook parts of the knitting needle, so as to selectively formstitches in one course knitted in the warp knitting machine and nostitches in another.
 2. Control device according to claim 1 comprisingat least two rotary control members rotatable at given speed forrespectively actuating the latch parts, on the one hand, and the hookparts, on the other hand, the control member for actuating the hookparts having more lifting lobes than the control member for actuatingthe latch parts.
 3. Control device according to claim 2 wherein at leastone of said rotary control members comprises a control chain havingindividual control links formed with lifting lobes.
 4. Control deviceaccording to claim 3 wherein at least another of said rotary controlmembers comprises a control cam.
 5. In a warp knitting machine withbipartite knitting needles respectively having a hook part and a latchpart, and provided with at least one needle bar for the hook parts andat least one latch bar for the latch parts of the needles, controldevice for controlling movement of the latch bar, said control devicecomprising means for uniformly and nonuniformly varying movements ofsaid latch parts in opening and closing the hook parts of the knittingneedle, for each course knitted in the warp knitting machine, and atleast two rotary control members rotatable at different speeds forrespectively actuating the latch parts, on the one hand, and the hookparts, on the other hand, the control member for actuating the latchparts being rotatable at a slower speed than the control member foractuating the hook parts.
 6. Control device according to claim 5 whereinat least one of said rotary control members comprises a control chainhaving individual control links.
 7. Control device according to claim 6wherein at least another of said rotary control members comprises acontrol cam.
 8. Control device according to claim 1 comprising at leastone patterning disc having a peripheral surface divided into a pluralityof control fields, each of said control fields being adapted to controldisplacement of the latch parts for each course knitted.
 9. Warpknitting machine according to claim 1 wherein the latch bar is dividedinto at least two parts along the length of the operating width thereof,said control device comprising separate control members for respectivelycontrolling displacement of each of the parts of the latch barindividually and independently of one another.
 10. In a warp knittingmachine with bipartite knitting needles respectively having a hook partand a latch part, and provided with at least one needle bar for the hookparts and at least one latch bar for the latch parts of the needles,control device for controlling movement of the latch bar, said controldevice comprising means for uniformly and non-uniformly varyingmovements of said latch parts in opening and closing the hook parts ofthe knitting needle, for each course knitted in the warp knittingmachine, and at least two control cams rotatable at the same speed forrespectively actuating the latch parts, on the one hand, and the hookparts, on the other hand, the control cam for actuating the hook partshaving more lifting lobes than the control cam for actuating the latchparts.
 11. In a warp knitting machine with bipartite knitting needlesrespectively having a hook part and a latch part, and provided with atleast one needle bar for the hook parts and at least one latch bar forthe latch parts of the needles, control device for controlling movementof the latch bar, said control device comprising means for uniformly andnoN-uniformly varying movements of said latch parts in opening andclosing the hook parts of the knitting needle, for each course knittedin the warp knitting machine, and at least two control cams rotatable atdifferent speeds for respectively actuating the latch parts, on the onehand, and the hook parts, on the other hand, the control cam foractuating the latch parts being rotatable at a slower speed than thecontrol cam for actuating the hook parts.